Measuring apparatus for the inside of bores



July 27, 1943.

D. a BENCH ET 1.

MEASURING APPARATUS FOR THE INSIDE OF BORES Filed Dec. 1, 1941 2 Sheets-Sheet 1 VIII/I, v QM mw m= E mlH um mm m /w/v//////z My 7,194s. D. E. BENCH Em 2,325, 9

MEASURING APPARATUS FOR THE INSIDE OF BORES Filed Dec. 1, 1941 2 Sheets-Sheet 2 IE. 7 I 3 3 .L '11! Imam-ens DAWD 'E. BENCH RTTORNEYS muwwsav W 0 ma;

' he tool of our invention with 'unitary element of the tool;

.diameterof.aizyiinder; v

Patented July 27, 1943 MEASURING Armani-Te riemnmsmt' OFBORESf- J David- E. Bench. and Melvin CmslivfDa-yton, I

Ohio, assignorsto Apco MossbergaGompany, Atatieboro, -,Mass., -a corporation .of ltlassachusetts ApplicationfDeeember 1, 1B 1,-' -1 9- 1 J 15 Claims. (G g-seems)- 'This' invention'reiates' to apparatus forgauging cylindrical 'b0res,'and.more particularly deals with a simple tool adapted for -field and shop use characterized by the fact thatits operating element is a one-piece structure having a unitary motion and free from weanqfrictional motion and backlash and having its parts arranged in i such fashion that it is" easily .assembiedglow in icest; light in weight, and easy .120 l handle.

j The-principal purpose of ourjiinventioniis to pr v de a tool t a due'to the..,simp1i.city ofits construction .and operation, isreadily adapted for nse in connection withloperations whereinit "2 necessary accuratelyto determine ,thejn'ternal eter of agtubu'lar or cylindrical element..."

' further purpose or our invention. haslheen provide a tool .ofiight weightandpontabie 1 raraeteristics adaptedforwfieldeand .shhfltvork wherein thelmeasurementpf .a boremaylbe read directly on a dial without the necessi-ty of. m me. matical computation or. calculation.

:A better understanding of. the principie. and application of. the measuring. apparatus -..of-. our

7 invention will'be had by reference to theamixed drawings in which:

Fig. 1 is a plan view of the. tooiofiollhinvention;

Fig. 12 is a diagrammatic-side.eievational lview,

' partly in cross section, showing .the' tool. :as .ap-

plied to. the measuring of .iihe interna1, ..di ameter of a cylinder;

'Fig; 3 isle, cross sectional viewalong "the line member 29, win-1e and attached at its edge fulcrum ma be suspended in 'a manner permitting adjusting of the sensitivityof the.

Referring now to the drawingsi-n detail. 2-!) is splittubular-casing} 2i and ZZ -arerigid contact pointsmounted on the exterior-thereoffzil' is-"a 'dial gauge; 26 is a' handief-an'dZE and'zfi areeiamping means adapted to holdthe two sections of the casing together when the tool is assembled.

i Referringmore partieula'rly to Fig. 2, '21 is a-fixed "beam firmly held inpos'it-ion by pivot 28 other endto movable Contact. 3i! -is a free" beam; fixedly mounted "at one end. thereofffon movable 1 con- 'tact'inember 2- 9 and='s'1idab1yassociated at its. other end with the operative"mechanism-of dial -auge-23 and the guide member" 31 Fixed beazn 27-is in contact with knife edg'e fulcrum 32 -and-asthe fixed contact elements 2| -2'2 a-hd'the movable contact member 29 are "brought into contact with" the inne surface of the cylindrical member 'i 33 the fixed beam 2'! fliig. '4 is across sectional view along. the .line

.Fi '5 is a diagrammatic.gperspective viewfjof part o'f'its cover removed; I.

Fig. 6is adiag-rammatic view of the operative Fig. 7 is a diagrammatic view of the operative unitary element of the tool showing its application in measi-iring the iinternai d-ia-meter of "a "cylinder;

. Fig. ',8;is a diagrammaticview, :partly-tbroken --away, of la-mod-ifiedform-ofrthe unitary operative -element of the itool; e i A :9 .is-a diagrammatic view of EtheC perati-Ve unitary-element of the tool shown iIl-.Fig.-.-8 showing .its application measuring-the internal i 0 shows aiurther modificationinfwhich the contact member is ,extensible.to. accommo date workpieces of various diameters; and

"Fig. =11-i-1iustrates.;a manner in whichtheknife wi11- flexaszrssiiteisbrought on the fulcrum 32-andtherebvthe free bear'r'i 30 is caus'edto move inwardly through-the guide member 3 I towards and against the operative mechanism or the dial gauge 23, wherebythe .amouhh of deiiection o'ffixed'beam 21 caused by' the Varia- *tmmn internal diameter of the tubular'member *3'3 denotdhyth'earrows-(1+1; in Fig. T'isi transmitted to'the nee beam 38, which, in turn, travels flongitudinal lythrough the guide member 3| to- *-wa-rds and-against the operative mechanism of --the dial gauge 2 3 to the extent denoted by the arrows b bin Fig. 7; This-travel or" movement of the free"beam.3 0 is directly converted into any desired numerical value andthe dial gauge 23 may beread directly to ascertain-the amount of deviation ff-rom'thedesired internal of the tubular n'1ember33.

' Referringnow to 'Figs. 8 and 9, 28is-the casing of the tool; 29 is the movable contact memdiameter 'portingo'ne-end' of the fixedbeam 2'1; 30' isthe .end .of thefif-ree beam' 30' are'fixedly held bra nember 3'4, which, in essence, takes the place (sofaras'thefixingoff the b'eam'ends is concerned) of the movable contact member 29 hereinbefore E described. The'contactinember 29' is held -in association j-with the "operative "element or the toolfby pin' 35; wh the tool isheld in uch v position that the movable contact member 23' merical value.

and; 11," the end of the d is closed by a cover 46 forthe purpose of protecting its operative mechanism.

.j-By reference to 1 it .is advantageous ,to

is perpendicular of the fixed beam 21 the inner contact point 36 of the movable contact member 29 rests on the fixed beam 21. When the tool is held in other positions the movable contact member 29' is prevented from falling out by the pin35.;

As will be noted by reference-to Fig. 9, when the movable contact member 29' is brought into operative contact with the'inner surface of cylin' der 33, the movable contact member 29. is forced downwardly and the contact point 36 presseson the fixed beam 21 whereby saidbeam is flexed downwardly about the fulcrum 32 Due to the connection between fixed beam 21' and free beam I moved within the bore.-

. application ofv our invention, but it will be under- 30' through element 34, as thefixed beam 21' arches downwardly the freebeam 30 is caused to travel away from the dial gauge 23' and this causes the movement of the operative mechanism of'the dial gauge 23' and gives a direct y reading of the difference in internal diameter of the cylinder 33 translated into any desired nustood that other means for fixedly mounting the fixed beam 2'! may be utilized according to indi vidual prefei'ence'and circumstances.

It'will be noted that, in essence, the tool of ourdnvention is actuated and gives direct readings according to the degree or amount of flexing It will be understood that whilethe travel of the free, beam 30 in Fig.- 7. is towards the dial gauge, that of the free beam-30 in Fig. -9 is away from the dial gauge. The same dial gauge may be used with either type of operative element so long as the dial gauge is marked off in the same manner on either side of the zero point.

This would mean that thetotal direct reading permitted by the-dial gauge would be definedon one-half ofrthe face area thereof. However, it

would be quite simple and satisfactory toqprovide ,a; tool having eachtype of operative element 3 .with an'appropriate dial-gauge adapted to give direct numerical readings over its entire face area.

Referrin tical elements 'as'inFigs. ,8 and 9. It vwill be noted, however, that the movable contact member; 25 of Figs. 8-and 9 takes another form. in'

-Fig.l0 As shown in Fig. 10, the contact member, 29' i provided; with an extensible member 3" whic h may-be extended or-reduced in length by adjustment of the-lock nut 38, whereby the over-all length of the contact member 29 may v be increased or. decreased accordingto the bore. to-be measured: This lends a high degree of 'adjustability to the tool of our invention and makes it adaptable for useon severalrelated jobs. It

is possible to provide this adjustable contact member -wi th micrometer adjustment(not shown) whereby its length may beset according to the a nature, of the individual operation to be performed." V Y j 1 In Fig. 11, 32 is the'knife edgefulcrum held means of shoulder means 39 and 40 and knurled knobs 4| and 42. It will be notedthat the apertures 43 through whichthe'thr eaded ends 44 and vJ55 of knife edge'fulcrum32; pass areof a diam- ;eter greater than that of. saidthreaded ends k44 and 45. This permits shifting the position-of the knife edge fulcrum 32, whereby the sensitivityof; the tool; may bevaried according to .the specific operation to -beperformed. L

toFigs. 2,,4,--

,. Aswill. be noted by reference v tool .opposite .its handle 4., it. will be notedi that within the bore to be measuredin order that now to'Fig. ld the numeral f, 21', 29', 32, 34, 3'5 andprcfer to the idenwhich is imposed by the movable contact member 29 on fixed beam 21. Since fixed beam 2'! is fixedly mounted at both ends, it will flex when it is brought tobear against the pivot. 32. This .causes. a relative shifting of the free beam 30 and causes the actuation of the operative mechanism of the dial gauge 23, whereby the dial gauge 23 will register; the amount of variation in the internal diameter of the borebeing tested in direct numerical values.

The distance across the three contact points may be predetermined for any given gauging job. In every instance, thisdistance would be in excess of the oversize limit of the bore and, as the tool entered the bore, animmediate deflection of the movable contact member would take place. This deflection, and all'variations encountered in rotating the tool or moving it axially of the bore, 7

wouldv cause .arching or deflection of the fixed beam 21 aboutthe knife edge fulcrum 32. Simultaneously thefree beam 30 would be arched and, due to the fixed relationship existing betweenthe beams 21 and 30 (as theyare fixedly mounted .on movable contact member 29), the free beam 30 would creep ,or travel towards the dial gauge and into operative cooperation with the indicating mechanism thereof, thereby giving the reading I V on the dial gauge.

The tool of our invention may be designed for specific-jobs or it may be constructedfor generaluse; If the tool is to be used for normal inspection, 'thedial gauge jm'ay 'be'marked of! in i in; place'against the walls of the casing 20 by,

have the tool centered.;..

thre areas, the central one specifying the limits or. tolerance permissible in the bore, and the areas on either side of this central area for oversized and undersized rejects. Inthis manner, the operator would be in aposition quickly to determine which bores are within the specific limits of tolf erance without having to make use of numerical values;

On the other hand, if the tool. is to be applied to universal or general use inthe shop or in the field, the dial gauge may be calibrated to give direct readings in fractions of an inch or millimeters or any other desired unit of measurement.

The use of the principle embodied in the gauging tool ofour invention not only permits the ':transfer"of.'the motion of the movable contact member through the dial gauge, but may very easily be adapted to magnify the original motion of-the movable contactmember. For example, in the particular example diagrammatically shown in Fig. '7, a magnification of approximately 2:1 is shown; in other words, thelinear movement of the movable contactmember 29 has caused a linear travel of the free beam 30 which is substantially-twice as great. 'I'lie-distanc'e traveled Y mid-calibration. riss gsugingweriepem ai g"; I i

byieach -these nemies re i and at is me -*catedbythearrows-d mand-12 b inFi -*cperation'of "the'gaugirrg' tool ofmur invention "will benea'dily apprecia-tedby 'thosesliilled dn the art. *The" operative mechanismbf 'om invention =issubs-t-ant'i'dHy ne'e -"from rrictionm -=motionand *issiifliciently sturdy towithstand-ordmaryshock and held "handling witnout losing the'degree"-of wen-"adapted for es-e in' fieldw rk fwi ere" t fis -necessaryqiiitkly*ariaaccurately-to ascertain the accuracy df bores-citationssortsend wheie more elaborate and helmets-gauging apparatus domot 'findready use becanse df their lack' olfsturdirfess iand' fsiiluref-toretain' a medterniined degre'e of -=aecur'acy. v

It wiH -be"iinderstood by tnesesnnes mtse it that the d 'ails =o'f "construction hei'etnbei orefle- L seemed-and ilinstrated in the amie'ined drawings may be varied to suit individual preferences 'and loeal o'ondition's. Weha-ve desci ibed' a speciflc 5nd :the eeepe 26f the appended amiss. 7 r 1 i-moilnted' at one end;=1a: free :beamnmassncianon with said flxed beafln gdrezindicating meansinna some-tibia "with: said nee 'beam; sand "work icon.-

=tacting means in associationwith said -flxedbearn. -2.' A :gauge cemprising: -an beam, pivotally mounted =at-one end a second beam? dn-mssocia 1.

-tion "with saidflrst inentioned beam i worlescom 'tactirig mans uniting onerend oiisaidifirst mentioned beam and the corresponding endof said second-beam in spaced relationship; and size indicatih'g liieans opefiitively associated with the free end of said second beam.

3. A gauge comprising: a flexible beam pivotally mounted at one end thereof; a flexible beam attached at one end thereof in spaced relationship with the end of said flrstly mentioned flexible beam opposite said pivotally mountedend; size indicating means operatively associatedwith the free end of said secondly mentioned flexible beam; and work contacting means in association with the spacedly attached ends of said beams.

4. A gauge comprising: a flexible beam pivotally mounted at one end thereof; a flexible beam attached at one end thereof in spaced relationship with the corresponding end of said flrstly mentioned flexible beam; size indicating means operatively associated with the free end of said secondly mentioned flexibl beam; and work contacting means in association with the spacedly attached ends of said beams.

A gauge comprising:- a flexible beam pivotally mounted at one end thereof; a flexible beam united at one end thereof in spaced relationship with the end of said flrstly mentioned flexible beam opposite the pivotally mounted end thereof; work contacting means in association with the spacedly united ends of said beams; fulcrum means in association with said firstly mentioned flexible beam; and size indicating means operatively associated with the free end of said secondly mentioned flexible means.

*6; A gauge conrplrislng a -=-ftlexible*beam-=pi-vot'alllymonrited at 'one"errd' thereo pivot-"means said *beam'; a second flexible bearn unite one erid thered'f -in spaced "rel end -s'" d flrstly menti'oned flexible edwpposi-te said pivot-ally *iriouhttfd "endy worle "tacting means i 'as-soci'a icnwiiith the-spacediy'u iited 'ends df said' beams' diilorom "'ineairs' association withsaid firs'tiy mentib'ned U *flex'iblebeam'iiit-ernrediate-saidpivot means '61 "said woi k F meeting-means: and size indicatmg riieans opei'eitiwely asso'cidtedaiiiththe ne er did "7. A gange i'conrprisingi a flexible beam' piv 'ota ily mounted 'o'ne'enii' thereof, pi vot means t e 11 said beam; a. second flex itill beam ttlymriit' ti r means operativelyassociatedwithithe end 7 n'dly m'entioned iflexlble opposite -the end soacedly united with said flrstly mentioned beam I 8 gau'ge comprising: a flexible beam iiu btallyimonnted at onerend the'reof; pi votnieans subi ortlng said: beamtecon ibl'e beam iitrxedlyimonnted'atrone en. islaticnshi-p with othei-rend'of aidrfirstlyzmention'ed flexible'ibeam'; tlilcrum' m s in associa- "tti'UII' W'ithKBEidIflPSH/Y 'ention'ed flexible'ibeam; wail ontaoting' imeahs an association with said ymenticiredr ble beam interim-ediate said o't .tmeans rsaid iul'crum' .means land nmounted ttconernl d-ithereofn iaivot means supporting said beam; 'a second flexible beam fixedly mounted at one end thereof in spaced relationship with the other end of said firstly so mentioned flexible beam; fulcrum means in association with said firstly mentioned flexible beam; work contacting means in association with c said firstly mentioned flexible beam intermediate said pivot means and said fulcrum means and 3 adjacent said fulcrum means; and size indicat- 7 ing means operatively associated with the free end of said secondly mentioned flexible beam.

10. A gauge comprising: a case; a flexible beam pivotally mounted within said case; pivot means 09 supporting said flexible beam; at second flexible beam fixedly mounted at one end thereof in spaced relationship with the other end of said firstly mentioned flexible beam; work contacting means invassociation with the spaced fixed ends of said beams; an aperture insaid case adapted to permit passage therethrough of said work'contacting means; fulcrum means in association with said firstly mentioned flexiblebeam intermediate said pivot means and said work contact- 7i) ing means; and size indicating means operatively associated with the free end of said secondly mentioned flexible beam mounted on said case.

, 11. A gauge comprising: a, case; a, handle at one end of said case; contact means fixedly 1'5 mounted onsaid case; a flexible beam pivotally spaced-rewerindicatm'gsmeanisacperativeiy associatedwvith .mounted within said case; pivot means support- ,ing said flexible beam; a, second flexible-beam fixedly mounted at one end thereof in spacedrelationship withthe other end of said firstly mentioned flexible beam; work contacting means in association with the spaced fixed ends of said beams; an aperture insaid case adapted to'per- .mit passage therethrough of said work contacting means; fulcrum means in association with said firstly mentionedflexible beam intermediate said pivot means and said work contacting means and adjacent said work contacting means; and size indicating means operatively associated with the free end of said secondly mentioned flexible beam. v

12. A gauge comprising: a case, a'handle at one end of said case; a plurality of contact members fixedly mounted on said case; aflexible beam pivotally mounted within said case; pivot means j supporting said flexible beam; a second flexible,

beam fixedly mounted at one end-thereof in spaced relationship with the other end of said flrstlymentioned flexible beam; fulcrum means in associationwith said flrstlymentioned flexible I beam ;'-work contacting means in association with said firstly mentioned ,flexible beam intermediate said pivot means and said fulcrum means; and size indicating means operatively associated with the free end of said secondly mentioned flexible beam,

13. A gauge comprising z a case; a handle at pivotally mounted within said case; pivot means supporting said-flexible beam; a second flexible i beam fixedly mounted att-one end thereof in spaced relationship with the other end of said firstly mentioned flexible beam; fulcrum means inassociation with said firstly mentioned flexiv ble beam; work contacting means in association with, said firstly mentioned flexible'beam intermediate said pivot means and said fulcrum means and-adjacent said fulcrum'means; and size indicating means operatively associated with the free end of said secondly mentioned flexible beam. l

, 14. A gauge comprising: a case; a handle at one end of said case; a plurality of, contact members fixedly mounted on said case a, flexible beam pivotally mounted within said case; pivot means supporting said flexible beam, said pivot means being -movably mounted onfsaid case; a second flexible beamffixedly mounted at one end thereof in spaced relationship with the other end of said firstly mentionedfleirible beam; work contact- .ing means in association with the spaced fixed endsof saidbeams, said work contacting means being adapted to be increased and reduced in length according] to the operation to be performed-; an aperture in said case adapted to permit passage therethrough of -said work contacting means; fulcrum means-in association with said firstly mentioned flexible beam intermediate said pivot means and said work contacting means, said fulcrum means being adjustably mounted on said case; and size indicating means operatively associated with the free end' of said secondly mentioned, flexible beam mounted on said case;

' 15. A gauge comprising: a case; a handle at one end of said case; a plurality of contact memone end'of said case; a plurality of -contact mem- :bers fixedly mounted on said case; a flexible beam bers fixedly mounted on said case; a flexible beam pivotally mountedwithin said case; pivot means in' association with the spaced fixed ends of said beams, said work contacting means being adapted to be increasedand reduced in length according to'the' operation to beperformed; an aperture in said case adapted to permit passage therethrough of said work contacting means; and size indicating means operatively associated with the free end of said secondly mentioned flexible beam mountedon said case.

1 DAVID E. BENCH.

1 MELV'INA. CROSBY. 

